Rotor for use in impact crushers

ABSTRACT

A rotor body is composed of a plurality of axially spaced parallel plates which are rigidly connected for rotation about a joint axis. The outer periphery of the rotor body is provided with slots extending inwardly of the periphery and in parallelism with the axis, and impact bars are arranged in the respective slots. Between the bars and one sidewall of each slot is mounted a support bar which interengages with the impact bar, the latter extending to some extent outwardly beyond the periphery of the rotor body. Between the other sidewall of the slot and the impact bar is arranged a wedge member which is urged to wedging position by a plurality of pressure-fluid operated elements arranged in the slots and being connected via branch conduits with main pressure fluid conduits arranged in the rotor body.

United States Patent Koenig et al.

ROTOR FOR USE IN IMPACT CRUSHERS Inventors: Rolf Koenig, Handorf; Gerhard Hemesath, Munster, both of Germany [73] Assignee: Hazemag Hartzerkleinerungs Und Zement-Maschinenbau-Gesellschaft mbH, Muenster, Germany Filed: Sept. 29, 1972 Appl. No.: 293,373

[30] Foreign Application Priority Data Sept. 30, 1971 Germany P 21 48 752.5

[56] References Cited UNlTED STATES PATENTS 3,645,459 2/l972 Lucas et al. 24l/l9l 2,747,803 5/1956 Hanse 24l/l9l FOREIGN PATENTS OR APPLICATIONS 678,428 9/1952 Great Britain 241/195 Jan. 8, 1974 [57] ABSTRACT A rotor body is composed of a plurality of axially spaced parallel plates which are rigidly connected for rotation about a joint axis. The outer periphery of the rotor body is provided with slots extending inwardly of the periphery and in parallelism with the axis, and impact bars are arranged in the respective slots. Between the bars and one sidewall of each slot is mounted a support bar which interengages with the impact bar, the latter extending to some extent outwardly beyond the periphery of the rotor body. Between the other sidewall of the slot and the impact bar is arranged a wedge member which is urged to wedging position by a plurality of pressure-fluid operated elements arranged in the slots and being connected via branch conduits with main pressure fluid conduits arranged in the rotor body.

10 Claims, 3 Drawing Figures PATENTEDJAH 1914 3784117 SHEET 2 [IF 2 ROTOR FOR USE IN IMPACT CRUSHERS BACKGROUND OF THE INVENTION The present invention relates to a rotor, and in particular to a rotor for use in impact crushers,

Impact crushers are, speaking in general terms, devices wherein a rotor is mounted for rotation at high speed in a chamber. The rotor is provided on its periphery with impact instrumentalities, usually impact bars, and the material to be crushed (e.g., rocks or the like) is admitted from above into the chamber so that it falls onto and is impacted by the impact bars of the rotor. There are impact plates provided in the chamber, being spaced outwardly from the periphery of the rotor and material which is impacted by the impact bars of the rotor is flung by them against the impact plates, and repeated impacting of material by the bars and the plates causes the crushing of the material.

It is quite evident that in a device of this type there is substantial and quite rapid wear of the various components, especially of the impact bars of the rotor. Because the efficiency of crushing of the material depends to an appreciable extent upon the condition of the impact bars, for instance the extent by which they project beyond the periphery of the rotor body, it is necessary to frequently adjust the position of the impact bars on the rotor to compensate for such wear, and if necessary to reverse the impact bars in their position so that previously unexposed portions of the bars become exposed for engagement with the material to be crushed. Even this is only a temporary measure, however, and quite frequently the bars must be completely replaced with new ones. All of these measures require, of course, that access be possible to the rotor and this is a requirement which as a rule is not readily satisfied. Usually, it is at least difficult to gain access to the rotor in the crushing chamber. This makes it difficult to perform the necessary manipulations, so that the adjustments are time consuming which, in turn, is disadvantageous because evidently the crusher must be shut down while the adjustments are being made. The difficulty of such adjustments is particularly emphasized if the impact bars are especially long or are of two or more sections, because pressure devices provided for the purpose of properly maintaining the bars in position, must be loosened, and these devices are usually pressure spindles which must be individually released and, when the adjustment or replacement has been carried out, must again be individually tightened.

It is, accordingly, an object of the present invention to overcome the disadvantages of the prior art.

More particularly, it is an object of the present invention to provide an improved rotor for use in impact crushers, which avoids the disadvantages.

Still more particularly it is an object of the present invention to provide such an improved rotor in which the adjustments necessary on the impact bars of the rotor can be carried out much more quickly and easily than heretofore possible.

in keeping with these objects, and others which will become apparent hereafter, one feature of the invention resides in a rotor for use in impact crushers, comprising in combination of rotor body means mounted for rotation about an axis and having an outer periphery. A plurality of slots extend inwardly of the periphery and each slot has a longitudinal orientation and parallelism with the axis of rotation. A plurality of impact bars are provided, each being accommodated in one of the slots and in part projecting outwardly beyond the periphery of the rotor body means. A plurality of sets of wedge members are provided, with the wedge members of each set being received in a respective slot spaced along the associated impact bar and wedging the latter for maintaining it against displacement relative to the slot. A plurality of said fluid-operated pressure elements are also provided, with the pressure elements of each set acting upon respective wedge members of an associated set of wedge members and urging them to wedging position. A plurality of pressure-fluid conduits are each associated with one of the sets of pressure elements for supplying pressure fluid thereto.

Thus, the wedge members which serve to minutely adjust and hold the position of the impact bars, are operated by action of the fluid-operated pressure elements, and all of the fluid-pressure elements which are associated with the wedge members of one of the impact bars are connected to a common pressure fluid conduit. This is a surprising construction, because in the environment in which the rotor of an impact crusher is necessarily utilized, it would appear that the pressure fluid conduits and the fluid-operated pressure elements could not be made properly tight to avoid loss of fluid, and would be subjected to damage which would cause them to leak or become destroyed. The present invention is based on the discovery that, quite contrary to this apparently justified initial assumption, it is possible to provide a construction which is such that the pressure exerted upon the wedge members can be maintained, at least until the next adjastment in the positioning of the impact bars or replacement of the impact bars is required. Furthermore, it is possible to associate the pressure system with hydraulic pressure reservoirs which are capable of compensating for small amounts of pressure fluid that might be lost during operation.

It is well known that wedge members used for the purposes herein discussed may be of the self-locking type or may be of the type which is not self locking. If they are of the self locking type then they will be retained in their wedging position once they have been pushed to this wedging position by the pressure elements. However, it is currently preferred to use wedging elements which are not of the self-locking type, simply because experience has shown that the wedging elements of the self-locking type will become so tightly wedged after only a few hours of operation of the rotor that they are very difficult to release when adjustments must be made. Inasmuch as the pressure elements act constantly upon the wedging elements when the device is in operation, it is possible and, as pointed out above, currently preferred to make the wedge elements of the non-self-locking type. This means that when the particular impact bar which is to be adjusted or replaced is located at an upper side of the rotor, that is when the rotor has been turned so that the impact bar and its as sociated wedge members are so located, termination of the supply of pressure fluid to the pressure elements of the wedge members which are associated with this particular impact bar will allow these wedge members to move downwardly under the influence of gravity, freeing the impact bar for ready adjustment, or at least requiring no more than a light hammer blow to move downwardly out of their wedging position. Advantageously, the pressure elements will be so installed that the direction in which they exert pressure bisects the wedging angle. This means that the pressure elements are protected against lateral forces and skewing of their pistons is thereby avoided.

The present invention makes it possible to release simuitaneously all of the wedge members associated with a given impact bar, or if the impact bar is for instance of two sections, to release the wedge members associated with both of the sections, or of only one of the sections as may be required. Conversely, pressure can again be exerted on all of the wedge members simultaneously. The end portion of the pressure fluid conduit supply pressure fluid to all pressure elements associated with the wedge members of a given impact bar can extend outwardly to one of the axial end faces of the rotor where they can be provided with appropriate connectors, for instance connectors of the snapcoupling valve-type or the like, by means of which they can be connected with a source of pressure fluid The arrangement of the couplings can be so chosen that they are particularly readily accessible for maintenance personnel. In this connection it will be appreciated that it is not absolutely necessary that the position in which maintenance is carried out on a given impact bar, requires for the impact bar to be located at the upper side of the stationary rotor.

Pressurizing of the pressure fluid conduits can be effected by means of a manually operated pump acting as a source of pressure fluid, or of course by a compressor, by a vessel containing pressure fluid under pressure or the like, and also the release of pressure from the conduits can be effected in a similar manner, with connection of the pump or the source of pressure fluid automatically opening a valve in the connector associated with the respective pressure fluid conduit.

It is possible to provide the rotor with a single pres sure fluid conduit which is connected by means of branch conduits with all of the pressure elements of the rotor.-. However, if as is currently preferred, the wedge members are not of the self-locking type, then such an arrangement would not be particularly advantageous because releasing of the pressure would simultaneously free all of the wedge members associated with all of the impact bars, not only those associated with an impact bar on which maintenance work is to be performed, and there is the danger that undesired displacement might take place of impact bars for which such displacement or other maintenance is not required.

Rotors of the type here under discussion are frequently made of two or more axially spaced parallel or substantially parallel rotor plates which are mounted on a common shaft and connected with one another so as to be rigid. If the rotor utilizing the present invention is of this type, then it is advantageous if the pressure elements are located within the respective cutouts, that is cutouts formed in the respective plates, so that they do not extend beyond the axial end faces of the respective plate and are thereby protected. Further protection for the pressure elements can be obtained by providing recesses in the respective plates, which recesses extend inwardly of the respective cutouts and which house the pressure elements so that only the pistons thereof are exposed for engagement with the wedge members. Alternately, appropriate casing or similar mounting elements may be provided which are appropriately secured on the plates and which house the pressure elements in the aforementioned manner. This makes it possible to use pressure elements of commerically available type which may not inherently be constructed to withstand the rigors of the environment in which the present rotor is to be used, but which can in this manner be sufficiently protected to make them so usable.

It is clear that the pressure fluid conduits must also be protected against damage. This can be carried out by providing the rotor, if it is of the rotor-plate type with branch conduit bores in the respective plates, and by connecting these bores with a common main conduit for each set of such bores associated with the respective set of wedge elements associated with the impact bar. The main conduits may extend in parallelism with the axis of rotation of the rotor and may for instance belocated in a tubular connector which rigidly connects the plates of the rotor to one another. However, it is also possible to provide protective plates or covers so that the conduits may be located outside the physical confines of the various rotor components and yet be protected against damage.

The impact bars are retained against undesired displacement in their respective slots not only by the wedge members but also by support bars which are lodged between the respective impact bar and one side face bonding the respective slot. According to the invention it is advantageous if the support bars are located on that side of the respective impact bars which is the trailing side as seen with respect to the direction of rotation of the rotor, with the wedge members and pressure elements being located at the opposite side. This is advantageous because the impact bars are thus reinforced at their trailing side and the surface of the impact bars which faces forwardly and which impacts the material to be crushed is particularly stable and can have a relatively large surface area extending over the entire length of the respective impact bar. This could not be achieved if the wedge members, particularly of the non-self-locking type, were to be located at the trailing side of the impact bars.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS:

FIG. 1 is an end-elevational view of a rotor according to the present invention, partly sectioned on line II of FIG. 2; I

FIG. 2 is an axial section taken on line II-.-II of FIG.

1', and

FIG. 3 is an enlarged sectional view of one of the pressure elements in FIGS. 1 and 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing the drawing in detail it will be seen that here the illustrated rotor is composed of four axially spaced parallel rotor plates 1 which are rigidly connected with one another by a tubular element 2 to which they may be welded or otherwise secured in nonillustrated manner, just as the rotor will normally be mounted on a non-illustrated shaft for rotation about the axis A (see FIG. 1). The plates 1 are all provided on the outer periphery with circumferentially spaced slots or cutouts 4 extending inwardly of the outer periphery and in each set of four of such cutouts (one in each plate 1) there is lodged an impact bar 3 which may be of one piece or, as shown in FIG. 2, of two longitudinally adjacent pieces. The direction of rotation of the rotor is identified with the arrow a in FIG. 1 and it will be seen that in each set of the cutouts 4 there is lodged, at the side of the impact bar 3 which is the trailing side thereof, a support bar 5 which extends over the entire length of the rotor and is welded to the plates 1. Each bar 5 has a longitudinally extending rib 6 which extends into an appropriately configurated groove provided on the associated impact bar 3.

Located at the opposite side of each impact bar 3 in the same cutout 0r slot 4 are the wedge members 7 which assure that this engagement of the rib 6 with the associated groove in the impact bar 3 is maintained.

The wedge members 7 are inserted between the sidewalls 8 of the respective cutouts 4 and the juxtaposed surfaces 9 of the associated impact bars 3, being inserted from the radially inner side as illustrated. It is advantageous that the wedge members 7 do not extend over the entire length of the rotor, but be provided in form of individual wedge members each having a length which advantageously is slightly greater than the axial thickness of the respective plate 1, thus slightly overhanging the plate at the opposite axial endfaces and, advantageously also at the outer periphery as suggested in FIG. 7. The purpose of this overhang is to protect the plates 1 in these regions which are subject to strong wear, to some extent.

Radially inwardly of each of the wedge elements 7 each of the cutouts 4 accommodates a hydraulic adjuster or pressure element 10, having a piston 11 which engages the inner side of the respective wedge member 7 and exerts an outwardly directed force, thus forcing the wedge member 7 to wedging position. Each of the pressure elements is associated with a branch conduit 12' which extends in direction approximately towards the axis A through the respective plate 1 (see FIG. 2) and all of these branch conduits 12 associated with a particular impact bar 3 are connected with a pressure conduit or main conduit 13 which extends in axial parallelism with the axis of rotation A and in the illustrated embodiment is located within the tubular connecting element 2 which protects it against damage. The conduit portion 13 extends to the outer axial endface of one of the terminal plates 1 (in FIG. 2 the lefthand one) where it is provided with a coupling member 15 which is readily accessible to an operator and is provided with a one-way valve to prevent release of pressure when the system composed of the conduits 12 and 13 has been pressurized.

It is possible also to locate the conduits 12 and 13 exteriorily of the plates 1 and the tubular connecting element 2, in which case protective plates or similar elements must be provided which surround them or which are at least located ahead of them as seen with respect to the direction of rotation a. In this case the conduit 13 can be extended straight over the entire length of the rotor to the point where the connector 15 is to be provided.

FIG. 3, finally, shows a detail of one of the pressure elements 10. These pressure elements each have a cylinder l6 and a hollow piston 11 which can be extended outwardly from the cylinder 16 under the influence of fluid pressure. The piston 11 is biased by a spring 17 which permanently tends to retract it into the cylinder 16 and does so when pressure in the hydraulic system 12, 13 is reduced or disappears. The cylinder 16 is provided with external screw threads 18 which are in engagement with similar internal screw threads provided in a recess of a mounting member 19, with a sealing ring 20 being interposed between the elements 16 and 19. The element 19 is welded to the respective rotor plate 1 and serves to protect the cylinder 16 against damage. If desired, the element 19 may be extended to the exposed endface of the cylinder 16, or may be provided with a collar which extends to that exposed endface, in order to provide additional protection for the cylinder 16.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in a rotor for use in impact crushers, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended 1. In a rotor for use in impact crushers, a combination comprising rotor body means mounted for rotation about an axis and having an outer periphery; a plurality of slots extending inwardly of said periphery and having a longitudinal orientation in parallelism with said axis; a plurality of impact bars each accommodated in one of said slots and in part projecting outwardly beyond said periphery; a plurality of sets of wedge members, each set comprising a plurality of wedge members received in a respective slot spaced along the associated impact bar and wedgingly engaged the latter for main taining it against displacement relative to the slot; .a plurality of sets of fluid-operated pressure elements, the pressure elements of each set acting upon respective wedge members of an associated set of wedge members and urging them to wedging position; and a plurality of pressure-fluid conduits each associated with one of said sets of pressure elements for supplying pressure fluid thereto.

2. A combination as defined in claim 1, wherein said pressure elements are hydraulic pressure elements.

3. A combination as defined in claim 1, further comprising a plurality of support bars each fast with said rotor body means and accommodated in one of said slots intermediate the respective impact bar and one sidewall of the slot; interengaging retaining portions on the respectively associated impact and support bars; and wherein said wedge members are accommodated intermediate the respective impact bar and an opposite sidewall of the slot.

4 A combination as defined in claim 3, wherein said wedge members are of the non-self-iocking type.

5. A combination as defined in claim 3, said wedge pressure elements being so oriented that the direction of the pressure exerted by them bisects the angle of said wedge members.

6. A combination as defined in claim 3, said rotor body means having opposite axial endfaces, and wherein said pressure-fluid conduits extend to one of said endfaces and are provided with couplings with automatic closing valves for connection to a source of pressure fluid.

7. A combination as defined in claim 3, said rotor body means comprising a plurality of axially spaced at least substantially parallel rotor plates, and connector means rigidly connecting said plates together, said slots each being composed of a plurality of cutouts provided in the respective plates and extending from one to the other axial endface of each plate; and wherein said extending within the respective plate to an associated pressure element.

9. A combination as defined in claim 8, said connector means comprising at least one tubular connecting member, and said main conduit portion being arranged within said connecting member.

10. A combination as defined in claim 7, said pressure elements each including a cylinder and a piston; and wherein said pressure elements are so mounted within holes of said plates that said cylinders are enclosed and only said pistons project from said holes. 

1. In a rotor for use in impact crushers, a combination comprising rotor body means mounted for rotation about an axis and having an outer periphery; a plurality of slots extending inwardly of said periphery and having a longitudinal orientation in parallelism with said axis; a plurality of impact bars each accommodated in one of said slots and in part projecting outwardly beyond said periphery; a plurality of sets of wedge members, each set comprising a plurality of wedge members received in a respective slot spaced along the associated impact bar and wedgingly engaged the latter for maintaining it against displacement relative to the slot; a plurality of sets of fluidoperated pressure elements, the pressure elements of each set acting upon respective wedge members of an associated set of wedge members and urging them to wedging position; and a plurality of pressure-fluid conduits each associated with one of said sets of pressure elements for supplying pressure fluid thereto.
 2. A combination as defined in claim 1, wherein said pressure elements are hydraulic pressure elements.
 3. A combination as defined in claim 1, further comprising a plurality of support bars each fast with said rotor body means and accommodated in one of said slots intermediate the respective impact bar and one sidewall of the slot; interengaging retaining portions on the respectively associated impact and support bars; and wherein said wedge members are accommodated intermediate the respective impact bar and an opposite sidewall of the slot. 4 A combination as defined in claim 3, wherein said wedge members are of the non-self-locking type.
 5. A combination as defined in claim 3, said wedge pressure elements being so oriented that the direction of the pressure exerted by them bisects the angle of said wedge members.
 6. A combination as defined in claim 3, said rotor body means having opposite axial endfaces, and wherein said pressure-fluid conduits extend to one of said endfaces and are provided with couplings with automatic closing valves for connection to a source of pressure fluid.
 7. A combination as defined in claim 3, said rotor body means comprising a plurality of axially spaced at least substantially parallel rotor plates, and connector means rigidly connecting said plates together, said slots each being composed of a plurality of cutouts provided in the respective plates and extending from one to the other axial endface of each plate; and wherein said pressure elements are each arranged in one of said cutouts inwardly of the respective axial endfaces.
 8. A combination as defined in claim 7, said conduits each including a main conduit portion extending in parallelism with said axis, and a plurality of branch conduit portions branching off said main conduit portion and extending within the respective plate to an associated pressure element.
 9. A combination as defined in claim 8, said connector means comprising at least one tubular connecting member, and said main conduit portion being arranged within said connecting member.
 10. A combination as defined in claim 7, said pressure elements each including a cylinder and a piston; and wherein said pressure elements are so mounted within holes of said plates that said cylinders are enclosed and only said pistons project from said holes. 